1. Field of the Invention
This application relates generally to acoustic systems and probes and, more specifically, to methods and systems for testing acoustic systems including ultrasonic probes and transducers.
2. Relevant Background
Acoustic (e.g., ultrasonic) imaging is an important technique that may be used at different acoustic frequencies for varied applications that range from medical imaging to nondestructive testing of structures. The techniques generally rely on the fact that different structures have different acoustic impedances, allowing characterization of structures and their interfaces from information embodied by the different scattering patterns that result. While most applications use radiation reflected from structures, some techniques make use of information in transmitted patterns also.
Transmission of acoustic radiation (e.g., acoustic waves) towards a target and receipt of the scattered radiation may be managed by modern acoustic-imaging systems, each of which may take a variety of forms. For example, many modern systems are based on multiple-element array transducers that may have linear, curved-linear, phased-array or similar characteristics and which may be embodied in an acoustic probe. Summing the contributions of the multiple elements that form a transducer array allows images to be formed. However, the failure of a small number of elements in a given array, or even of a few defective receive channels in the acoustic system itself, may not be readily perceptible to users because of the averaging effect of summing many elements to form an acoustic beam. Furthermore, the failure of even a small number of elements or receive channels can significantly degrade the performance of acoustic imaging systems, notably in certain modes of operation like those known as “Doppler” or “near-field” imaging modes.